Object.prototype.delClassName = function(classN) {
	var className = this.getAttribute('class');
	className = className.replace(classN, "");
	this.setAttribute("class", className);
}

Object.prototype.delClassName = function(classN) {
	var currentClassNameArray = this.classList;
	currentClassNameArray.remove(classN);
}

Object.prototype.addClassName = function(classN) {
	var currentClassNameArray = this.classList;
	currentClassNameArray.add(classN);
}